The present invention is directed to bicycles and, more particularly, to various features of an apparatus for controlling a bicycle device.
Bicycle devices that are operated by an electric motor or the like recently have become known. For example, the rider may manually operate an electric switch, and the signal produced by the switch may be used to operate a motor that upshifts or downshifts the bicycle transmission accordingly.
One known bicycle transmission control device includes separate upshift and downshift switches that are separately wired to their corresponding derailleur control units. Such a system increases the amount of hardware that must be mounted to the bicycle. Other known bicycle transmissions include a single wire that carries the electrical signals for both upshifting and downshifting the transmission. In these systems, the upshift and downshift signals differ in some way. For example, in an analog system, a +6 volt signal may be used to signal an upshift operation, and a +3 volt signal may be used to signal a downshift operation. Alternatively, a +5 volt signal may be used to signal an upshift operation, and a −5 volt signal may be used to signal a downshift operation. In a digital system, multibit digital messages that address a particular device and specify the desired operation may be serially communicated on a single wire. In either case, complex calculations must be performed to determine the requested operation with accuracy. In the case of analog systems, the control signals may deteriorate as a result of moisture caused by riding in rain, riding through a puddle, etc.